Improvement in furnaces



ATTORNEY CMB.l FIELD. `Furnaoes- WITNESSES www -N www 4 Sheets-Siloam..

G. B. FIELD.

Furnaces.. I

No. 212,366. Patented Feb. 18., 1879..

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llllIlliIl WITNE`SSES 4 sheets-sheen s. G. B. FIELD.

Furnaces.

Patented Feb.1s,1879.

lNvENTQR (5H TORNEY' ITN ESSES Ohmaw/ NA PETERS. PHOTO LITNOGRAPHE 4 sheets-sheet 4.

G. B'. FIELD.

Furnaces.

No. 212,366'. Patented Feb. 18,1879.

ATToRNEY To all whom it may concern:

, New York, in the UNITE.. STATES PATENT Duuren.

GEORGEA B. FIELD, OF YORK, N'. Y.

IMPROVEMENT IN FURNACES..

Specification forming part of Letters Patent No. 212,366, dated February 18, 1879 application iiled l June 29, 1878.

Be it known that I, GEORGE B..FInLn,^of county of New York and State of New York, have invented certain new y. and useful Improvements in Furnaces; and I do hereby declare the following to be a full,

clear, and exact description of the invention, such as will enable others skilled in the artfto which it pertains to make and use it, reference bein g had to th e accompanying drawings, which form part of this specilication.

My invention relates to an improvement in furnaces for steam-boilers and other purposes.

The object of the invention is to commingle air in jets with the gases escaping from the burnin g fuel, whereby all un consumed products of combustion contained in the gases as they iiow from the main or primary chamber may be ignited and consumed in the throat of the furnace.

A further object of my invention is to regulate the supply of air to the hollow perforated air -receptacles located in the combustionchamber, in order that the desired amount of oxygen may be supplied to the gases result ing from the combustion of fuel in the furnace.

A further object of the invention is to supply heated jets of air to the fire-box of a furnace at a point below the surface of the fuel, and thus cause the air to become thoroughly heated'and impregnated with carbon before it commingles with the flame of the burning fuel.

Another object of the invention is to thoroughly protect the perforated air-receptacles from" contact with the fuel, and thus prevent slag or cinders from adhering to and clogging the apertures in said air-receptacles.

A further Objectis to conduct water from the boiler through suitable pipes or conduits located in front of the air-receptacles, and discharge the steam from said pipes into the steam-space of the boiler.

Another object of my invention is to store heat in a bridge-wall in rear of the kair-receptacles, for reheating the air and gases as they are commingled and iiow through and over said bridge-wall, and to the several ends in view as above specified.

. My invention consists, iirst, in the combie nation, with the lire-box of a furnace, of a` series of hollow air-receptacles having small apertures, leading through the walls thereof, the lower portions of said air boxes or receptacles being located nearly or quite in the same plane as that of the grate-bars, whereby air is supplied to the air-receptacles and issues therefrom in jets into the fuel, and valso into the spacerabove the fuel, in close proximity to the bridge-wall of the furnace.

My invention further consists in the combination, with the fire-box of a furnace, of heated air-receptacles having corrugated or serrated sides, and small apertures extending from the interior of said receptacles into said corrugations or serrations, whereby the gases as they flow between said air-receptacles are deflected by the corrugations and intimately intermixed or commin glcd with the small jets of heated air issuing from the air-receptacles.

My invention further consists in the combination, with the lirebox of a furnace, of a series of hollow air-receptacles and a damper or regulator, for supplying air to each one of air-receptacles of the series, as aforesaid.

My invention furtheronsists in the combination, with a series. of hollow perforated airreceptacles located in the rear portion of a furnace fire-box, of a water-grate placed in front and in close proximity to said air-recep tacles, said water-grate serving to prevent the direct contact of the burning fuel with the airreceptacles, and thus obviate the collection of cinders or slag upon the outer surface of the air-receptacles, and prevent the free flow of air therefrom.

My invention further consists in the combination, with a series of hollow perforated airreceptacles located in the rear portion ofa rebox, of a watergrate placed in front and in close proximity to said air-receptacles, and a water-supply pipe leading from the boiler to one end of said water-grate, and a steam-supply pipe extending from the other end of said water-grate to the steam-space of the boiler.

The invention further consists in the combination, with the fire-box of a furnace, having hollow perforated air-receptacles located'in the rear portion thereof, of an open work employed for such purpose.

bridge-wall in rear of said air-receptacles, for imparting heat to the air and gases owing through the same.

My invention further consists in the-several details in construction and combinations of parts, as will hereinafter be described, and be pointed out in the claims.

In the accompanying drawings, Figure l is a longitudinal vertical section of a furnace embodying my invention. Fig. 2 is a front elevation, and Fig. 3 a transverse vertical section, of the fire-box. Fig. 4 is a plan view of the bottom of the fire-box. Fig. 5 is a transverse vertical section taken on a line passing between the perforated air tubes or receptacles and the bridge-wall. Fig. 6 is a transverse vertical section through the perforated air-receptacles. Fig. 7 is an enlarged view,

in perspective, of one of the air tubes or chambers. Fig. 8 is a vertical section of the latter. Figs. 9 and l() areenlarged views of the feeding hoppers or chutes.

A. represents a steam-boiler, of anydesired form, and B are the walls of a furnace. Crepresents the grate-bars, which may be stationary', or provided with means for shaking5 the same, as desired.

plane with the grate-surface, for the admission of a slicing-bar, to remove the vclinkers from the grate.

F represents air tubes or receptacles, made of fire-clay or other suitable heat-resisting material, the construction of which is clearly'illustrated in Figs. 7 and 8. Each tube F is formed with an interior chamber, b, extending from its lower end nearly to its upper end.

The outer sides of the tubes or chambers are provided with any desired number of corrugations or serrations, c, the outer edges, c", of which project toward theflre-box when the tubes are in proper position.

d are small perforations, leading in a diagonal direction from the interior chamber, I), to the series of corrugations c. Any desired number of tubes or chambers F are arranged on the supporting cross bar or plate G, while their upper ends rest-in contact with a partition, e, of fire-clay, which extends upwardly around the boiler, and prevents the passage of gases from the fire-box at a point above thel perforated air tubes or chambers. The cross-ba-r or plate G is rmly secured to the side walls of the furnace, and-is preferably provided with a flange, f, which serves asa support for the rear ends of the gratebars, although a separate cross-bar-may be Supportingplate Gis formed with air-ports g, which correspond in number and size to the openings Hymer chambers in the air-tubes F, and register therewith.

To the lower surface of the supporting-plate is secured, by suitable-lugs or equivalent devices, a sliding damper, H, which latter is also provided with openings h, equal in size and number to the openin gs or air-ports g in Through the front wall, D,- of the fire-box E is formed an opening, a, on a the supporting-plate G. Sliding damper' H may be operated by a bar orl rod, I, fulcrumed in the perforated post t', and adapted to be connected with a stud, i', on the lower side of the damper; or, instead of having the damperrod extend beneath the grate-bar, it may be placed on the outer side of the furnace-wall, and have one of its ends connected with the sliding damper by a link.

I do not limit myself to any particular means for operating the damper, as many devices may be resorted tofor such purpose.

By opening the damper, so that its air-openings will register with the air-ports in the supporting-plate, warm air from beneath the burning fuel on the grate-surface will iiow upwardly into the several .air tubes orchambers, and from thence issue, in smallminute jets, iuto the passages j between said air chambers. The jet-openin gs are arranged diagonally, for the purpose of increasing their length, and thus subject the air to greater heating-surface -as it flows through the fire-clay heatingichambers or tubes. As the jets of highly-heated air come in contact with the gases of combustion, which contain a large percentage-.of unconsumed carbon, the air and said gases are thoroughly comrningled and intermiXed,1thus causing-the ignition and complete combustion of all unconsumed products of combustion l iu the gases flowingv from the main orprima-ry combustion-chamber.

By reason of the fact'that the air-jets issue from the corrugations formed in the outer sur faces of the air tubes or chambers,.a more thorough blending. and intermingling ,of lthe air and gases is in-sured,:as the gases. are deflected, by the ridges forming lthe corrugations, into the grooves, .from Wheneeissue theinnumerable minute air-jets, and the-gases are momentarily-detaiued or confined, whilethe jets of air force the inflammable mixture outward into the spaces between the tubes or chambers.

As the air-supply tubes or chambers practicallyform the rear wall of the fire-box they are consequently subjected to aniintense heat, which is requisite tofraise thetemperature of the air to the required degree ytopromote the most perfect combustion. burning fuel is but slightlybelow the-upper ends of the air-supply-tubes or chambers, and hence the air must percolate vthroughr'thefincandescent coal before it passes through the spaces between the air-tubes or chambers. 1f

the coal should bepiledup againstA ithe airsupply chambers 4the intense heatwould soon operate to depositclinkers and slag upon `the surface-of the air-chamber, and, by clogging the minute air-openings, soon render` the-apparatus inoperative. To obviatethis diiiculty I'place a grate, K, immediately in front and in close proximity` to the air-chambers,fortthe purpose of preventingtheburnin g fuel .from coming in immediate Nvcontact with 'the airtubes.

When my improved furnace is not employed in generating steam the grate may becom- The level of the,

posed of fire-clay, of such construction that it may be readily renewed when necessary. When the furnace is connected with a steamgenerator grate Kis hollow and lled with water from the boiler. Itmay be formed of upper and lower cross-pipes, L 7c', and vertical connecting pipes or tubes I, although it' constructed to other like forms itwill answer the desired purpose. The lower pipe ol' said water-grate K connects with the water-space of the boiler at its forward end by a pipe, L,

while the upper cross-pipe is provided with vpipes M, which extend through the heat-fluelVl', beneath the boiler, and connect with the grate preserves the air-chambers from contact with the burning fuel, and hence obviates theY deposition of clinkers or other substances onl said tubes, which would vhave the effectof cloggingthe air-openingsinsaidtubes. Again, the water is heated and converted into steam by the heat, which would be but partially utilized otherwise, thus allowing of increased heating-surface to be added to a boiler at a small increased expense. By adding to the number-of pipes M the heating-surface can be increased until all available space in the flue M -is' utilized. Agaim this arrangement of water-grate and connecting-pipes insures the most perfect circulation of water in the steamboiler, as well as in the water-grate itself, and thus prevents the accumulation of scale in such parts.

N represents the bridge-wall, the front face, n, of which is perpendicular. Said wall is composed of a 4lattice or` open brickwork, whereby the air and gas, after owing through the spaces between the air-supply tubes or chambers, enter into a secondary combustionchamber, O, between the bridge-wall and the rear surfaces of said air-tubes. rEhe bridgewall is made perpendicular instead of on a rearward incline, as is common, in order that the air and gases shall be upwardly deflected and mingled together within the chamber O. By constructing the bridge-wall of open brickwork the air is caused to percolate through the wall;.and as a large amount of heat may be stored in the open brick-work, the temperl ature of the air and gases will be kept equable and at the highest practical point of temperature.

P'arehoppers or feeding-chutes attached to the front of the furnace, and are employed in lieu of doors. Each hopper is provided with a sliding front plate, p,which may be raised or lowered, as desired to regulate the draft. Instead of the sliding plates they may have a swinging, revolving, or sliding damper, combined with a rigid front plate. The fuel is face of the grate-bars.

placed in these hoppers, onefor inore'being used, and from there forced into the fire-box without the necessity of admitting cold air to the fire-box. As the hopper or chute should always be kept filled, the air entering through the hoppers must pass through the fuel contained therein. By raising the front plates, p, more or less air will be admitted directly to the sur- This method of feeding fuel to the furnace is an important feature in connection with my other improvement hereinbefore referred to, as it is desirable that the sides of the fire-box shall be practically closed, in order that any excess of air over and above that which passes through the grates shall be admitted to the tire-box in minute jets and-in such quantities-as shall promote the most perfect combustion of all unconsuined products of combustion, which ordinarily escape through the stack. As heretofore sta-ted, the exact quantity of air necessary for this purpose can be regulated and admitted hy means of my improved airchambers and dampers connected therewith.

My improvement is adapted to be applied to any style of furnace, either for the boilers of stationary, portable, or locomotive engines, or for furnaces used for purposes other than the generation of steam; and in use itis most eifectu'al in preventing smoke, by reason of the fact that the unconsuined products of combustion in the gases ilowin from the fire-box are all ignited and consumed before they reach the uptake.

I would have it understood that I do not limit myself to the exact construction and arrangement of parts shown and described, as many slight changes might be -resorted to without departing from 'the spirit ofvmy invention. f

Imake no claim to the particular construction of feeding-chutes in this patent; but reserve thel right to secure a separate` patent for the same.

Having fully described my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. The combination, with the fire-box of a furnace, of a series of air-supply chambers located in the rear end thereof', and arranged to form intervening lspaces for the passage of the gases from the fire-box to the smoke-stack, said air chambers or tubes having interior chambers and small perforationsleadin g therefrom through `the wall or walls of the tubes or chambers, the lower ends of said tubeslbeing placed below the upper surface of the bed of fuel on the grate-bars, substantially as set forth.

2. rI he combination, with the fire-box of a furnace, of a series of air-supply-tubes o1;vk chambers arranged to form intervening passages forthe escape of the lgases to the smokestack, located opposite the fuel-space and in front ofthe bridge-wall of the furnace, substantially as set forth.

3. The combination, with a supporting-plate imity tosaid chambers, and

having any desired number of air-ports therein, of a series of hollow perforated air chambers or tubes having their open lower ends arranged to register with the air-ports in` the f supporting plate or bar, substantially as set forth.

- 4.. The'combination, witha series of hollow perforated air-supply chambers or tubes, of a supporting-plate, provided with air-ports, and a sliding damper attached to said supportingplate and adapted to regulate the admissionV of air to the hollow perforated chambers,l sub= stanti-ally as set forth. f 5. The combination, with a series of hollow perforated chambers or tubes, the lower ends of which are practically on the same plane as thel grate-bars, of a close partition 'between the boiler, the furnace-walls, and upper ends of the air-chambers, substantially as set forth. 6. The combination, with the re-box of a furnace, of a series of hollow perforated air- Isupply chambers located. at ythe rear end of the fire-box, the outer surfaces of which are wholly or partially corrugated in vertical lines, substantially as set forth.

7. The combination, with the fire-box of a furnace, of a series of air-supply chambers located in front of the vbridge-wall, andarran ged to form intervening spaces for the passage of the gasesv from the fire-box to the smoke-stack,

said air-chambers provided with vertical cor-A lrugations on their outer surface, and with di- `vagonal air-passages leading from the inner chambers to said corrugations, substantially as set forth.

8. vThe combination, with a'series of hollow perforated air-supply chambers or tubes arranged-opposite the fuel space in front of the bridge-wall of a furnace fire-box, of an openwork grate or shield located inclose-proxserving to -pre- -ventthe fuel from resting against said channbers, substantially as set forth.

9. .The combination, with a series of hollow perforated air-supply chambers loc-ated in` front of the bridge-wall, of a hollow water grate or shield located in closel proximity to said chambers, and furnished with water Yfrom the steam-boiler, substantially as set forth.

10. The combination, with a series of hollow perforated air-pipes or chambers located in front of the bridge-wall, of a hollow grate located in close proximity to said chambers, and pipes connecting said grate with the steam and water spaces of a steam-boiler,` substan- 1 tially as set forth.

1l.` The combination, with a series of air- `supply chambers or tubes located in front of the bridge-'Wall and ahollow grate located in close proximitythereto, of a pipe for conducting waterfrom one end of theboiler to the grate,-and one or-more pipes for connecting the shield with the steam-space at the opposite end ofthe boiler,-=substantially as set forth.

v12. rI he combination, with `a series ot'- airsupply chambers located in front ofthe bridge- J une, 1878.

GEORGE B..FIELD. Witnesses:

Trios. IZRI'r-GHIE, ALF. VALLAT. 

